Look up pictures of Arequipa, Peru and you’re bound to see El Misti volcano towering somewhere in the background. Although the neighboring Chachani volcano is taller, El Misti is the most iconic. The moment clients step off the plane in Arequipa and see that single cone-shaped peak dominating the skyline, they will understand why.

While discussing which volcano would be best to climb, a fellow teacher I worked with at an English institute in Arequipa told me, “I feel like El Misti is staring at me as much as I’m staring at her.” With a few weeks left in Peru and enough time to hike only one mountain, I knew it had to be El Misti.

My friends and I planned a weekend trek and shopped around at the tour agencies in Arequipa for the best package. Since we were going to be hiking in July, which is in the height of winter in Peru, we needed snow jackets and pants, sleeping bags and tents — all of which you can find at just about every tour company that offers volcano treks.

On a Saturday, we arrived at the tour office, loaded up our gear and set off in a Jeep. At about 10 a.m., our group started hiking from the base of El Misti. Aside from having to schlep our heavy packs, the first leg of the hike was easygoing. The weather was mild and the incline gradual. After an hour or so, I put on my gloves, a scarf and a chullo (an Andean beanie with earflaps made from alpaca wool). As we got higher, it got even colder, and our breaks became more frequent as we adjusted to the altitude.

We made it to base camp around 4 p.m., where we set up our tents and ate dinner before going to bed at 6 p.m. in preparation for our midnight wakeup call. Make sure your tour operator provides a high-grade sleeping bag, especially if your clients are hiking in the winter.

Our start time went from midnight to 1 a.m. as we roused ourselves out of our tents and resumed our climb. About an hour into the hike, a woman in our group succumbed to altitude sickness. As one of our guides accompanied her and her boyfriend back to base camp, I briefly considered joining them. Although I wasn’t feeling sick, the altitude made every step difficult as each breath provided less and less oxygen. I am not the athletic type, but I found that this didn’t really matter. My friends — the rugby player and the gym enthusiast — struggled equally to press on at such a high altitude. While clients should be fit enough for the hike and prepared for the cold weather, the altitude is certainly the most physically demanding aspect of the climb.

We continued hiking through sunrise, which provided a stunning view of Arequipa with the mountain’s surreal triangular shadow stretching over the city. After trudging on for a few more hours, we stopped just short of the summit to attach crampons to our boots before crossing the snowy slope to the top.

With icy winds pounding our faces, we pushed through the last stretch and sat down on the rocks for a break. From the summit, you can hike another hour or two to the cross at the peak. The crater, on the other hand, is just over a small slope a short walk away. Exhausted from the journey, we opted to just see the crater. We took pictures at the crater’s edge, where we could see and smell sulfuric steam rising from the active volcano.

The hike back down is considerably shorter and can be done by late afternoon on the second day. Having a good guide here is key, as hikers make their way down the snowy slope instead of following the rocky trail up the mountain. Tread carefully, wear crampons and listen to the guides to avoid slipping on any packed snow.

Once back at base camp, we packed our bags and headed down to the bottom of the mountain to meet our driver. We were back in town by 6 p.m., where we shed our hiking boots and warmed our toes, satisfied that we had conquered El Misti.

What to bring: Large bottles of water, snacks (such as chocolate and nuts). Tents, packs and sleeping bags/mats can be rented from the tour company.

Avoiding altitude sickness: Chew coca leaves (which can be bought at any market), drink plenty of water and pace yourself while hiking. There is also preventative medicine available at pharmacies in town.